The invention relates to a process of generating usable energy from parallel flows, especially from wind flowing from any direction at any speed and from changing directions at changing speeds, according to the pre-characterising part of the main claim; it also relates to a device for carrying out said process.
The process and device in accordance with the invention are suitable for exploiting very low speeds of flow from approximately 1.5 to 2 m/s and are able to utilise the energy at all wind speeds. The wind conditions prevailing at the sites selected for applying the process in accordance with the invention are of less significance; however, it is important to ensure that the wind can flow freely against the devices in accordance with the invention. The invention is particularly advantageous for supplying individual houses or higher buildings, with the device in accordance with the invention being positioned thereon, making use of the existing structures.
For generating electric energy it is known to erect and operate wind power generators with rotors with greater diameters. The disadvantages of such systems refer to the erection expenditure on the one hand and to the energetic limitations on the other hand. Under conditions where the wind offers maximum output values, the operation of such systems has to be discontinued or they are easily destroyed. If the installed electric output is increased, the rotor diameter has to be increased, which leads to technical vibration-related problems and sound emission, and the risk of rotor blades being fractured cannot be excluded. For lower output values there is a prior art wind power generator with vertical rotor blades, which accepts high wind speeds. By means of concentrating devices it was attempted to reduce the diameters of the rotor blades, such devices achieving higher flow speeds in the region of the rotor. In this context, advantage is taken of the analogy existing between electrical engineering and flow technology. Said analogy consists in that an electromagnetic field in a wire conductor bent in any way and a flow field around a vortex filament of any shape are described by the same relation, i.e. Biot-Sawart's law.
DE-PS 33 30 899 describes an assembly in the case of which air foils are arranged in a circle in front of a wind turbine, as a result of which there is generated a vortex coil because vortex filaments are torn out of the freely flowing wind by the air foils and induce a flow field which increases the speed of the axial flow. Small rotor diameters achieve high output values, the amplification factor ranging between 6 and 8. The disadvantage of this system is its high expenditure so that only a small test system is known. With increasing wind speeds, the vortex generating elements or air foils become unstable and require additional structural measures. Said assembly according to the state of the art has never been used commercially. From US 4 452 562 there is known a tornado wind turbine comprising a vertically arranged wind tower with a longitudinal aperture to allow the wind to enter tangentially. The upper end of the tower is open and the lower end comprises a through-flow aperture which is followed by a wind chamber exposed to the wind. A turbine is arranged in the through-flow aperture. The wind tower comprises double walls, with the space between the walls being connected to the wind chamber, thereby allowing flow conditions to develop in said space. The lower region of the inner wall of the wind tower is porous, allowing the radially flowing air to cooperate with the air flowing into the wind tower tangentially. This results in a vortex which emerges at the upper end, forms a vacuum core and sucks the air through the aperture in the wind chamber via the turbine. This assembly is disadvantageous in that it requires very large structural components in order to achieve the desired effect.